1. Field of the Invention
The invention is directed to a method for the production and/or processing of a web-shaped material, particularly paper, with at least one preferably traversing measuring system which records m measurement values per measurement position over the width s of the web-shaped material at n different measurement positions within a fixed time interval Δt.
2. Description of the Related Art
Measuring systems of the type mentioned above have been known for many years particularly in the paper producing industry, where they are used for ongoing process control and quality control.
Problems arise in the previously known systems due to the fact that the known measuring systems ultimately generate an enormous quantity of individual measurement values or measurement profiles in the form of graphs showing a plurality of recorded measurement values, and these measurement values or measurement profiles are subsequently subjectively interpreted typically by production supervisors. In so doing, the measurement profiles which show either measurement values which are recorded one after the other at the same measurement position (longitudinal profile) or measurement values of adjacent measurement positions transversely over the web of the web-shaped material (transverse profile) are allotted particular importance because they allow a highly focused search for tendencies in production.
Precisely with this in mind, European Published Patent Application No. 1 473 407 A1 suggests a method for generating two-dimensional charts—see FIGS. 1 and 2 of the cited document—of webs of a sheet-like material such as paper or foil which have been generated beforehand. On the one hand, each chart for illustrating longitudinal profiles and transverse profiles of different measurement parameters has a very high information content; on the other hand, for this very reason, they are subject to a variety of possible interpretations. The second approach in the above-cited document, to show overlapping and possibly also cyclical events in production by means of a plurality of transverse profiles, points in exactly the same direction: a large quantity of numerical values is generated which are ideally portrayed two-dimensionally and which must subsequently be interpreted, which requires a great deal of individual experience.
The subject matter of the somewhat older International Published Patent Application No. 03/072 874 A1 is ultimately directed to a control device for optimizing fiber orientation in paper production. To this end, the previously recorded measurement values for fiber orientation with respect to the feed direction and transverse direction of the paper web through the machine is fed to the control device. Then, by manipulating the set values of the machine, the control device is supposed to optimize the fiber orientation for the paper web to be produced by means of known fuzzy logic. The aim of this known document is not to provide quality numbers as a decision-making basis for determining papers which are or are not suitable for use.
Finally, International Published Patent Application No. 2010/080 869 A1 suggests a method for providing a probability model in which probability profiles are computed from a plurality of recorded measurement value profiles for previously determined and adjusted machine parameters in order to facilitate decisions on the part of the machine attendants for the optimal setting of machine setpoints based on the provided probability profiles. Again, in no way does this document aim at providing quality numbers as a simple basis for decision for determining papers which are or are not suitable for use.
To summarize, the methods known from the prior art assessed above have previously been suitable for using data obtained from measurement profiles directly within the internal production process or, more so, to readily display these data particularly in complicated two-dimensional graphs. The information obtained in this way is diverse, but is extremely difficult to interpret and analyze. But even when the production supervisors whose job is to interpret recorded measurement profiles have many years of on-the-job experience, the results of this interpretation are still often speculative and always highly subjective and are therefore dependent upon attitude and/or personality and are ultimately also not reproducible. In particular, a persistent problem consists in that a uniform production control based on the subjective interpretation of measurement profiles depends upon the individual interpretive ability of particular persons whose departure from the enterprise represents an ever-present risk.
For an enterprise, this dependence on persons is always highly risky. It is also always unsatisfactory to base industrial production on measurement profiles which are interpreted subjectively and under time pressure.